A comparison of different methods to assess the hemorrhagic activity of Bothrops venoms

The hemorrhagic activity of Bothrops (B.) alternatus, B. ammodytoides, B. j araraca, B. jararacussu, B. moojeni and B. neuwiediii venoms from specimens captured in Argentina was assayed after i.d. injection to mice. The hemorr hagic haloes produced by each venom hail different color intensities, altho ugh no significant differences were observed by measurement of the average diameters or the weight of the excised hemorrhagic haloes. Conversely, impo rtant differences were found by measuring the amount of hemoglobin extracte d from excised hemorrhagic haloes of similar size produced by different ven oms. The relationship between the amount of hemoglobin extracted and the we ight of the excised hemorrhagic haloes was linear, with a slope (hemoglobin released per gram of hemorrhagic halo) characteristic for each venom, and proportional to the potency. On this basis, the activity of B. alternatus, B. ammodytoides and B. jararaca is similar, about 1.5 times higher than tha t of B. jararacussu and B. moojeni venoms and threefold higher than that of B. neuwiedii venom. Thus, measurement of the of hemoglobin released provid es additional information in comparative studies, and may be used to assess the antihemorrhagic potency of antivenoms. (C) 2000 Elsevier Science Ltd. All rights reserved.